Has anyone done videos/pics of how test roms work?

[TSB]

I'm just getting familiar with Galaxian boards.
I picked up a couple nonworking PCBs so that I can learn about them & repair one as a spare for my cab.

I haven't jumped in yet, just cleaned the PCB, replaced rom sockets, and verified continuity on the pins.

I wanted to try out the test roms, but can't find documentation on what they 'should' look like when running properly (or with errors).


Here's what this board is doing:

 

[TSB]

Same scenario. Only the sockets have been replaced and traces verified:

 

[jacklick]

I have done a couple videos using the test rom. Not able to give you specific video with time stamp at the moment but if click on my signature it wont be hard to find.


Your 2nd video looks good except at the end when one, then, two three etc galaxians will fall from top left of screen to the right.

Check input and out pins of sprite/attack ram in row 1.


First board is probably resetting, check pin 26 on cpu.

Go to 49min here to see the galaxians fall

https://youtu.be/u6ukYPUh4WM

 

[Lurch666]

This is where mame can come in handy.
just rename the test rom and put it into a folder with the other galaxian files and try it with mame.

 

[philmurr]

All the test ROMs I've done follow a similar format:-

- test whatever RAM it can (and report its status) - programme RAM, object RAM (if it can read it) and video RAM (or banks for e.g. Mr Do and Phoenix/Pleiads)

- show sprites on the screen (if relevant) as you can't read the status of sprite RAM on Galaxian, Scramble etc.

- and on the newer ones, show status of DIPs and inputs (I must update the rest of the test ROMs to do this)

Your top board isn't booting and doesn't even get through the programme RAM check

As jacklick says for the 2nd Galaxian board, it should show sprites dropping down the screen once it's completed the VRAM test

You can run the test ROMs in mame if you know how to disable the checksum failure, but bear in mind e.g. Scramble hardware isn't properly emulated in mame so there may be differences when run on proper hardware

 

[mecha]

I just downloaded the Galaxian test rom. I wanted to hear that obnoxious beeping whine sound again. I was able to simulate ram errors by enabling various cheats. RAM STUFFED

on Galaxian you apparently replace the galmidw.u rom... interesting that they used the Midway rom names for the Namco set..?